The invention relates to a shearer loader for underground mining, comprising a shearer loader body, comprising a respective cutting drum, fastened to a supporting arm, for each direction of travel of the shearer loader, comprising drive motors for moving the shearer loader and for moving the cutting drums, comprising at least one cooling water circuit for cooling the drive motors, comprising a spray system which comprises a spray water circuit having a respective feed line to the tools of the cutting drums, comprising a preferably common water connection for the water circuits, and comprising valves assigned to the water circuits for switching the water circuits on or off.
In the underground winning of minerals, in particular in underground coal winning, the spraying of spray water via nozzles onto the working face to be worked is prescribed for the suppression of dust. In this case, the longwall spraying is largely effected by means of the powered support assemblies, to which nozzles are attached at suitable points, such as the canopies for example, and these nozzles can be operated with high-pressure water at about 150-200 bar. Reference is made only by way of example to DE 195 37 448 A1.
With the increase in output effected in shearer loaders, the generation of dust and the risk of explosion in cutting operations increase. Whereas initially the cutting drums were sprayed from outside via water nozzles from the supporting arm, internal spraying, in which a water nozzle which can be supplied with spray water is assigned to each tool at the cutting drum, is also taking place in the meantime. The picks are sprayed at pressures of up to about 50 bar.
The lower water consumption of the spray systems which is achieved by the internal spraying in the meantime enables some of the cooling water to be directed away from longwall again in hoses via the cable trailing chain (cf. www.steinkohleportal.de).
DE 30 200 46 A1 discloses a shearer loader in which the water fed to the shearer loader is divided at a line branch point into a line branch for the cooling water circuit and a line branch for the spray water circuit, wherein both line branches are fed, downstream of the units to be cooled in the water circuit and downstream of volume regulating valves in both sub-circuits, to a 4/3-way directional valve in order to be able to carry out the spraying, as a function of the direction of travel of the shearer loader, at the respectively leading cutting drum solely with the water flowing in from the spray water circuit and at the trailing cutting drum solely with the water fed to the cooling water circuit. Since less dust to be controlled by means of the spraying collects at the trailing drum, the spraying at the trailing drum is to be effected only with the lower water volume from the cooling water circuit.